Stark Broadening of Spectral Lines by High-Velocity Charged Particles

The broadening of the Lyman $\alpha$ line by high-velocity charged particles is calculated in the classical path approximation without the completed-collision assumption. For noninteracting perturbers, the divergence at large impact parameters associated with usual impact theories does not arise. Interactions between the perturbers are introduced by the pair correlation function. The resulting line shape is valid for frequencies larger than those permitted by the impact theory.